#include<reg52.h>

sbit ENA = P1^0;
sbit IN1 = P1^1;
sbit IN2 = P1^2;

void main()
{
    for(; ;)
    {
        unsigned int i, j = 60;;
        IN1 = 1;
        IN2 = 0;
        
        for(i = 0; i < 200; i++)
        {
            while(j--);
            ENA = ~ENA;

        }
    
    }
}